RELATION OF CAFFEINE AND ASPARAGINE. 171 



also, by the addition of oxygen and the elements of 

 water, yields the elements of taurine : 



1 at. asparagine = C 8 N 2 H 8 O 6 

 6 at. water . . = H 6 O 6 



8 at. oxygen . = O 8 



C 8 N 2 H 14 20 

 = 2 at. taurine . = 2 (C 4 NH 7 O 10 ) 



The addition of the elements of water and of a cer- 

 tain quantity of oxygen to the elements of theobromine, 

 the characteristic principle of the cacao bean (theo- 

 broma cacao), yields the elements of taurine and urea, 

 of taurine, carbonic acid, and ammonia, or of taurine 

 and uric acid : 



1 at. theobromine C 18 N 6 H 10 O 4 \ ... 



10 4 ( J 4 at. taurine . . C 16 N 4 H 28 O 40 



&& at. Water . . . Xl 2 oV/22 / == I i r^ in n r\ 



1 < 1 at. urea . . . C 2 N 2 H 4 O 2 

 16 at. oxygen . . O 16 ) 



C 18 N 6 H 32 42 &tf#t/fo 



or, 



1 at. theobromine C 18 N 6 H 10 O 4 \ t 4 at. taurine . . C I6 N 4 H 28 O 40 

 24 at. water . . . H 24 O 24 > = < 2 at. carbon, acid C 2 O 4 



16 at. oxygen . . O 16 ) ( 2 at. ammonia . N 2 H 6 



8 at. water ... H 8 O 8 > = 



C 18 N 6 H 34 O 44 



or, 

 1 at. theobromine C 18 N 6 H IO O 4 



~~ ^ 1 at. uric acid . C 10 N 4 H 4 O 6 



14 at. oxygen 



C 18 N 6 H 18 26 C 18 N 6 H 18 26 



87. To see how the action of caffeine, asparagine, 

 theobromine, &c., may be explained, we must call to 

 mind, that the chief constituent of the bile contains only 

 3-8 per cent, of nitrogen, of which only the half, or 1*9 

 per cent., belongs to the taurine. 



Bile contains, in its natural state, water and solid 



